Hey! Those stalls are discouraging... Of course, I'm not a nutritionist or doctor, so I can't really tell you what to do. You didn't say how long you've been "stuck" at this weight, but if it's less than 2-4 weeks, then it's not officially a plateau.
My thought, just looking at your height and weight, is that you shouldn't go lower. I'd say, stay with the program you have now and give it more time.
I think 50% protein would be very high--my own preference is to try to get 100 grams of protein when I'm exercising that much daily, and to keep my percentages of nutrients 30/40/30, protein/carb/fat.
Good luck! Don't give up! Hang in there!
Jay